Heat exchanger



Dec. 12, 1933. HA SEN 1,938,589

HEAT EXCHANGEH Filed April 22, 1931 3 Sheets-Sheet l INVENTOR (WA/91195 C HANSEN BY M f ,4. m.

ATTOR Y5 Dec. 12, 1933. c. c. HANSEN 1,938,589

HEAT EXCHANGER Filed April 22, 1931 3 Sheets-Sheet 2 INVENTOR (WAR .55 C. l/AA/Sf/V Dec. 12, 1933. c. c. HANSEN 1,938,589

HEAT EXCHANGER Patented Dec. 12, 1933 UNITED STATES PATENT OFFICE HEAT EXCHANGER Application April 22, 1931. Serial No. 531,942

Claims. (01. 257224) This invention relates to plumbing installations or systems, or more particularly to heat exchange installations. Certain features of the invention, however, are not limited to heat exchange installations and have various other applications in plumbing systems.

In various plumbing installations or systemsit is often desirable to connect two conduits to a chamber for the flow of fluid to or from different parts of the chamber or to connect two conduits for the circulation of different fluid mediums respectively with a chamber and with an element within said chamber. In order to effect this result, it has heretofore been necessary to out or otherwise form two openings in the chamber and to connect the two conduits with the chamber at these respective openings. By this method of procedure two joints are formed between the respective conduits and the chamber, each of which must be made fluid tight. In the case where one of the conduits is connected with an element within the chamber, a third joint is formed between said conduit and the element which also must be made fluid tight. The cutting of the several holes in the chamber and in the element and the forming of the fluid tight joints takes a great deal of time and also requires considerable skill and care, particularly in the setting of the joints, and this adds materially to the cost of the installation.

In heat exchangers of the type comprising an outer casing through which a fluid medium is circulated and an inner element mounted within the casing through which a fluid medium of a different temperature is circulated, serious stresses on the parts are produced by the relative expansion and contraction of the casing and the interior element and these stresses often produce leakage at the joints between the pipes for the circulation of the g fluid mediums and the casing and the interior element.

One object of the present invention is to improve the construction of fittings foruse in plumbing systems and to produce a fitting construc-' ticn which will enable two conduits to be. connected with a chamber with the expenditure of much less time, labor, skill and care than has been heretofore required.

Another object of the invention is to produce a fitting construction which will enable two separate conduits to be connected with a chamber by making only one opening in the chamber and only one joint between the chamber and the fitting.

Another object of the invention is to improve the construction and mode of operation of heat taken substantially on the line 51 5 of Fig. 4;

exchangers of the above type, and to produce a.

construction in which no serious stresses on the parts will be produced by the relative expansion, and contraction of the outer casing and the interior element.

With the above and other objects in view, the invention comprises the novel and improved features, constructions and combinations of parts hereinafter described and particularly pointed out in the claims, the advantages of which will be readily understood and appreciated by those skilled in the art.

The invention will be clearly understood from the accompanying drawings illustrating the invention in its preferred form and the following detailed description of the constructions therein shown.

In the drawings' 7 Fig. l is a view partly in front elevation and partly in vertical section illustrating the present 7 fltting construction applied to a heat exchanger;

Fig. 2 is a View in horizontal section taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a detail sectional view taken sub-I stantially on line 3--3 of Fig. 1;

Fig. 4 is a view in side elevation illustrating one of the sections of the interior element; i

Fig. 5 is a detail view in horizontal section and I as:

Fig. 6 is a view partly in front elevation and partly in vertical section illustrating certain features of the invention in modified form.

As stated above, the invention is illustrated in this application as embodied in a heat exchanger comprising an outer casing and an inner element respectively for the reception of fluid mediums of different temperatures. This heat exchanger construction is particularly designed to be embodied in a hot water heating system forheating water for domestic use or in condenser mechanisms. This construction,.however, is'not limited to these particular applications, but certain features thereof may be embodied in other heat exchanger constructions.

The device illustrated in the drawings coin-. prises an outer casing 2 for the reception of a fluid medium and an inner velements mounted within the casing for the reception of. a fluid me dium of a different temperature.

The outer casing is preferably made of sheet metal and has the shape in cross section shown in Figs. 1 and 2. The casing is preferably made of two similarly shaped concavo-convex portions 6 and 8, respectively, having marginal flanges 10 .1

and 12. These portions of the casing are assembled with their concave faces in opposed relation and with the marginal flanges in contact and are secured together by welding or bolting said flanges to each other. The portions 6 and 8 of the casing may be readily formed by stamping the same from sections of sheet metal.

The inner element 4, as shown, comprises two hollow sections 14 and 16, arranged in parallel relation and provided at their respective ends with suitable pipe fittings 18 secured together and to the sections to form conduits at the oppo site ends of the element connecting the sections in parallel. At each end of the element, one of the pipe fittings 18 is closed at its outer end by a cap 20.

Each of the sections 14 and 16 is preferably formed of sheet metal and has the shape in cross section and side elevation shown in Figs. 2, 4 and 5. Each section is made up of two similarly shaped concavo-convex half sections 22 and 24, arranged with their concave faces in opposed relation. The half sections are provided with marginal flanges respectively indicated at 26 and 28, and with inner flanges 30 and 32 arranged to be brought into engagement in assembling the half sections. The half sections are secured together preferably by Welding together the flanges 26 and 28, and the flanges 3G and 32. Each of the sections is provided with a longitudinal slot 34 extending throughout the greater part of the length of the section. This slot gives longitudinal flexibility to each section to absorb strains produced by the relative longitudinal expansion and contraction of the casing and the interior element.

In the present construction means are provided for supporting the inner element within the casing and for delivering the respective fluid mediums to and discharging the same from the casing and the inner element which necessitates forming only two openings in the casing. As shown in the drawings, such means comprises fittings 35 embodying certainnovel and improved features. Each of these fittings embodies a body 36 preferably substantially cylindrical in form and having a passage 38 extending longitudinally through the same. Each of the cylindrical ends of the body of the fitting is preferably threaded and, as shown, one end thereof is inserted in an opening 40 formed in the side wall of the casing 2. The fitting is secured to the wall of the casing by means of securing rings 42 threaded upon the body of this fitting upon opposite sides of the adjacent portion of said wall, and set up tightly against said wall. The casing is preferably provided with an outward bulge 44 having a wall portion 46 extending inwardly toward the axis of the opening 40 which conforms substantially to a plane, said wall portion being arranged to be engaged by the collars 42 to form a tight joint.

Fig. 2 shows the sectional formation of each of the fittings 35. As shown in this figure, each fitting is provided with a wall formation integral with the body 36 of the fitting providing a second passage 48 therein. This passage is formed by a tubular wall 50 located within the outer wall of the body 36 of the fitting. The portion of the wall 50 adjacent the left-hand end of the body 36 is substantially concentric with the outer wall of the body and is supported within said body by bridges 52 extending between said outer wall and said wall 50. The tubular wall 50, at a point between the ends of the fitting, is deflected out- Wardly from the axis of the body and joins the outer wall of the body portion, as shown in Fig. 2. This tubular wall 50 also extends radially outwardly beyond the outer wall of the body, as shown clearly in Fig. 2, and is preferably threaded as shown in this figure. The left-hand portion of the tubular wall 50 is extended beyond the c 'esponding end of the body of the fitting and is threaded for insertion in a correspondingly threaded opening in one of the fittings 18. Thus the left-hand portion of the passage 48 extends longitudinally through the lefthand portion of the body of the fitting and said Figs. 2 and 3, the passage being sufiiciently large at all points to allow a compartively rapid circulation of the fluid medium therethrough.

Thus it will be seen that, to attach each of the fittings to the wall of casing and thereby connect the passage 38 with the casing for the circulation of a fluid medium and to connect the inner tubular wall 50 of the fitting and thereby the passage as with the inner element for the circulation of another fluid medium, requires the formation of only one opening in the casing. The 1" is attached to that portion of the casing wall surrounding said opening and the inner tubular portion extends through said opening into the interior of the casing.

As shown in 1, two fittings are attached to the casing 2 and connected with the interior element. One of the fittings 35 is attached to the upper part of the casing 2 on one side thereof and the other fitting is attached to the lower part of the casing on the opposite side thereof. The inner tubular portion of one fittii connected to one of the sections of the interior element at one end of said element and the inner tubular portion of the other fitting is connected with the other section of the interior element at the opposite end of said element. This provides for the efficient circulation of the fluid through the casing and also for the efiicient circulation of fluid of a different temperature through the sections of the interior element.

When the construction shown is used for heating water for consumption in a domestic hot water heating system, the outer ends of the bodies of the fittings are connected by suitable pipes with the boiler of a furnace or other source of hot water or steam, and the tubular portions 50 extending radially outward from the respective bodies of the fitting are connected by suitable pipes with a hot water supply tank.

In the above construction serious stresses or strains on the parts which might be produced by the expansion and contraction of the metal of the inner element are obviated by the formation of the sections or" said inner element with the longitudinal slots 34. During the heating and cooling of each of the sections of the inner element, it is found that each of the slots 34 readily permits the deflection or bending of the parts of the section in directions to expand and contract the slot transversely. This bending of the metal in directions to expand and contract the slot, while it amounts to only a few thousandths of an inch, is sufficient to compensate for the expansion and contraction of the metal of each section, and there will be very little, if any, longitudinal expansion or contraction of the sections. Thus there will be very slight, if any, strains placed upon the joints between the fittings and the interior element or upon the joints between the ttings and the casing the expansion and contraction of meal or" the sections.

5 shows fitting construction differing substantially from that shown in Figs. 1, 2 and 3 applied to a heat exch nger of somewhat different form from that in these figures. In the construction shown in 6, the heat exchan er comprises an outer casing 52, and an inner element 54, consisting of a pipe coiled in a spiral formation, with the axis of the coils extending longitudinally of the casing 52, and with the coils spaced to permit the circulation of the fiuid in the outer casing about the coils. The end portions of the pipe are attached to the respective fittings 55 to support the element 5 within the casing.

Each of the fittings shown in Fig. 5 comprises a body indicated at 56, having a cylindrical 58, engaging within an openin ed to portion of threaded end the casing 52 and seem wall of the casing about opening by means 1 nuts 69 mounted on the threaded end of the fitting upon opposite sides of the wall the casing. The fitting is provided with a passage 62 extending lon itudinally through the body of the casing and through the end portion 53 thereof. The fitting is provided with a radial exten sion 64 to which is connected a short pipe section 65 by means of a threaded collar 66. Within the extension 64 and the pipe section 65 is formed a passage 68 communicating withthe passage 62 in the body of the fitting.

Within the passage 62 and extending axially therethrough is a pipe 70 of considerably smaller diameter than said passage. This pipe is connected to, and preferably formed integral with, the adjacent end portion of the pipe of the inner element 54. The end of the pipe '70 remote from the casing 52, is preferably flared, as indicated at 72 and engages a correspondingly shaped seat formed on the reduced portion '14 of the fit ng. This flared portion of the pipe 70 is engaged upon the outer side thereof by a correspondingly shaped seat formed upon the nner end of a short ipe section '76 secured to the portion '74 of the fitting by means of a threaded collar 78. Thus the flared end of the pipe 7 is securely held between the portion 74 of the fitting and the inner end of pipe section 76.

As shown in Fig. 6, one of the fittings 55 is secured to the wall of the casing 52 at one end thereof, and another fitting is secured to the wall of the casing at the other end thereof, and the respective end portions of the pipe forming the inner element are connected to the fittings in the manner described. This provides for the eificient circulation of the fluids of different temperature respectively through the outer casing and through the inner elem nt. Each fitting 55 is provided on the side thereof opposite the extension 64 with a here or passage having a threaded wall, which, as shown, is closed by a plug threaded into the bore. By removing this plug, the fluid within the pipes above the be drained therefrom.

Thus each of may 10. Harv the fitting. This capability of adjustment greatly facilitates the setting up of the heat exchanger in different installations.

It is to be understood that the invention is not limited to the particular construction and arrangement of parts of the illustrated embodiment of the invention, but that the invention may be embodied in other forms within the scope of the claims.

Having explained the nature and object of the invention and having specifically described a device embodying the invention in its preferred form, what is claimed is:

l. A heat exchanger having in combination a casing for the circulation of a fluid, having an opening at each end thereof, an inner element for the circulation of a fluid of a different temperature suspended within the casing, and having a series of coils, a fitting at each end of the casing for suspending the inner element within the casing, each fitting having a tubular portion secured to the margin of the casing about one of said openings and a second tubular portion extending through said first tubular portion into the casing and having its wall rigidly attached to the wall of said first portion, and a connection between the second tubular portion of each fitting and the inner element to suspend the inner element within the casing.

2. A heat exchanger having in combination a casing for the circulation of a fluid having an opening at each end thereof, an inner element for the circulation of a fluid of a difierent temperature suspended within the casing and having a series of coils, a fitting at each end of the casing for suspending the inner element within the casing, each having a tubular portion secured to the margin of the casing about one of said openings, and a second tubular portion extending through said first tubular portion into the casing and having its wall rigidly attached to the wall of said first portion and having a passage extending through the latter wall, and a connection between the second tubular portion of each fitting and the inner element for suspending the inner element within the casing.

3. A heat exchanger having in combination a casing for the circulation of a fluid having openings therein, a heat exchange element for the circulation of a fluid of a difierent temperature suspended within the casing and having a series of coils, fittings for the delivery and discharge of fluid to and from said casing and for the delivery and discharge of fluid of a different temperature to and from said element, said fittings each having a tubular portion passing through one of said openings in the casing, devices on said tubular portion for clamping between them the adjacent wall of the casing to form a tight joint, a second tubular portion arranged within the first tubular portion and extending through the latter into the interior of the casing, and a connection between the latter tubular portion and the heat exchange element to suspend the element within the casing.

4. A heat exchanger comprising a casing for the circulation of a fluid having openings therein, a heat exchange element for the circulation of a fiuid of a different temperature suspended within the casing and having a series of coils, coupling devices for the delivery and discharge of fluid respectively to and from said casing and for the delivery and discharge of fluid of a different temperature respectively to and from said element, each coupling device having a pipe passing through one of said openings, means on said pipe for clamping between them the adjacent margin of the casing to form a tight joint, a second pipe arranged partially within the first pipe and having its wall attached to the wall of said first pipe and having a passage arranged to receive or deliver fluid through the latter wall, and a connection between each of the latter pipes and the element for suspending the element within the casing.

5. A heat exchanger comprising in combination a casing for the circulation of a fluid having an opening at each end thereof, an inner element for the circulation of a fluid of a difierent temperature suspended within the casing and having a series of coils, a fitting at each end of the casing for suspending the inner element within the easing, each fitting having a tubular portion secured to the margin of the casing about one of said openings, said inner element having at each end an extension projecting through the said tubular portion of the fitting and rigidly attached at its outer end to the wall of the fitting to suspend the element Within the casing, and a tubular portion extending from the body of the fitting having a passage constituting a continuation of the passage through said extension.

CHARLES C. HANSEN. 

